<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=<device-width>, initial-scale=1.0">
    <link rel="stylesheet" href="sass/3.css">

</head>
<body>
  <div id="app" class="app">
    <div class="input">
      <input type="text" v-model:value="counter" class="cin_item">
    </div>
    <div class="content">
      <div>
        <div class="item" @click="counter +=0">0</div>
        <div class="item" @click="counter +=5">5</div>
      </div>
      <div>
        <div class="item" @click="counter +=1">1</div>
        <div class="item" @click="counter +=6">6</div>
      </div>
      <div>
        <div class="item" @click="counter +=2">2</div>
        <div class="item" @click="counter +=7">7</div>
      </div>
      <div>
        <div class="item" @click="counter +=3">3</div>
        <div class="item" @click="counter +=8">8</div>
      </div>
      <div>
        <div class="item" @click="counter +=4">4</div>
        <div class="item" @click="counter +=9">9</div>
      </div>
    </div>
  </div>
</body>
<script src="https://unpkg.com/vue@next"></script>
<script>
  const Counter={
    data(){
      return{
        counter:0
      }
    }
  }
  Vue.createApp(Counter).mount('#app')
</script>
</html>